Anyone rebember the threading tool grinding fixture that was posted awhile back? Seems like it was posted by John Stevenson, and was used on a surface grinder. I tried to search the archives, but the old boy has posted so much, I can't seem to be able to sort it out.

I owe ya a cold one. Er, as some of you guys on the other side of the pond prefer, a warm one.

Regards,
TC

Carld

01-14-2007, 02:20 AM

I finally gave up and posted my first photo on this site as seen below. I have not tried to do it here but what the heck, a photo is the best way to describe something.

Forrest Addy

01-14-2007, 05:06 AM

I've been grinding threading tools free-hand all my working life except when I've needed matched tools for repetative tooling reasons.

Why suddenly do we need a grinding fixture again?

kap pullen

01-14-2007, 10:53 AM

Forrest,

Maybe Tim hasn't been hand grinding threading tools all his life?

I have been grinding them for 35 years too, but the eyes are going bad.

I believe it will help the hobbiest to make some of those chores just a bit easier.

Kap

Lew Hartswick

01-14-2007, 12:23 PM

Here is one I made a few months ago.
Hope this works, first time to post a picture here.
http://home.earthlink.net/~lhartswick/threading.jpg
If i'm lucky.
...lew...
nope not lucky. more research necessary.:-)
I guess it did work just took a little longer.

Carld

01-14-2007, 01:43 PM

http://i82.photobucket.com/albums/j276/yeathatshim/P1010002copy.jpg

Here is my grinding fixture. It starts as a 2 1/2" cube of cold roll. The base is machined to a 5 deg angle. The slots are machined at 30deg on each side and set screws are added to hold the tool. You can make it any size you need for as big a tool you will grind but I found 1/2" tools is big unough.

I can grind by hand but with the fixture it is perfect and very sharp. Gives me a reason to use the surface grinder too.

Tim Clarke

01-14-2007, 08:01 PM

Well, I have one that works. One of the things I've been going to do for awhile.

Forrest: you are absolutely right, hand ground threading tools are easy for those who have worked in the trade, in times past. No doubt, you served an apprenticeship under a tough taskmaster who taught you the finer points of grinding all manner of cutting tools. I respect your skills. I admire them. Those of us that are home shop types sometimes struggle with the details of doing nice work. Trying to take my work to the next higher level, I have noticed that georgeous threads, shiny and fitting nicely seem to elude me. I want to see if the cutting tool is where the problem lies.

Lacking a local mentor who has skills such as yours leads me to get by the best I can. This in no way should be construed as an apology. I'm pretty damn proud of how far I've progressed. I guess I'm trying to explain how it is for those of us that have never worked in the trade.

Best Regards
Tim

Spin Doctor

01-14-2007, 09:48 PM

I've been grinding threading tools free-hand all my working life except when I've needed matched tools for repetative tooling reasons.

Why suddenly do we need a grinding fixture again?

I can think of one reason why. I prefer to use a quick change type tool post or even just a square block type set square to the Z Axis of the lathe. That way I know the angles on the lead and trailing side of the tool bit are dead nuts. I've ground more tools off-hand than I care to think about and will grind a lot more before I'm done. But I was always taught to work smarter not harder.

Tin Falcon

01-15-2007, 10:57 AM

I too learned in trade shool to grind tools I still use hss tools for most of my work at the home shop. I have ground threading bits for internal and external threads. I have however surcumb to modern tecnology by investing in an Aloris bit for the threading tool holder. I figure it will last a lifetime in the home shop. The beauty of this is the angle is built in just dress the top as needed. Also you can reverse the spindle and use the bottom of the tool and thread left handed.